Thomas redshank squirrel
| Thomas redshank squirrel | ||||||||||||
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| Funisciurus anerythrus | ||||||||||||
| ( Thomas , 1890) |
The Thomas redshank squirrel ( Funisciurus anerythrus ) is a species of squirrel from the genus of the redshank squirrel ( Funisciurus ). It occurs in parts of West and Central Africa.
features
The Thomas redshank squirrel reaches an average head-trunk length of 16.7 to 19.8 centimeters, the tail is 15.0 to 17.0 centimeters long. The weight is around 190 to 240 grams. The rear foot length is 42 to 46 millimeters, the ear length 15 to 16 millimeters. It is a medium-sized squirrel with a brown fur on the back that is interspersed with gray and beige. On the sides of the body there is a single pale sand-colored stripe that extends from the shoulders to the torso and is bordered in brown on the underside. The peritoneum consists of dense hair and can be gray, white or red-orange in color. The color of the head corresponds to the back, the eyes are framed by a narrow sand-colored line above and below and the ears are small. The front and rear legs are pale sand-colored, the toes have clearly pronounced claws. The tail reaches about 85% of the head-trunk length. It has long hair and is banded reddish at the base, black towards the back and equipped with a white tip. When viewed from below, the tail appears reddish, when viewed from above it appears dark with white frost. As a rule, the tail is curled up over the body when the animals are resting, and pointing straight up with the tip of the tail pointing backwards when the animals are moving. The females have two paired teats (0 + 0 + 1 + 1 = 4). The chromosome set of the animals consists of 2n = 38 chromosomes (FN = 62).
| 1 | · | 0 | · | 2 | · | 3 | = 22 |
| 1 | · | 0 | · | 1 | · | 3 |
The skull has a total length of 46.1 to 49.0 millimeters and a width of about 25.7 to 27.1 millimeters. Like all species of the genus has the type in the upper jaw half per one to a incisor tooth formed incisor (incisor) to which a tooth gap ( diastema follows). This is followed by two premolars and three molars . The teeth in the lower jaw correspond to those in the upper jaw, but only with a premolar. In total, the animals have a set of 22 teeth. The bony palate ends at the anterior margin of the last molars.
The Thomas redshank squirrel is particularly similar to the firefoot squirrel ( Funisciurus pyrropus ), with which it sometimes occurs sympatric . This is slightly larger and has a longer snout, the legs are light to pale red and the peritoneum is white.
distribution
The Thomas redshank squirrel occurs in the west coast of Central Africa from the high altitudes in the southwest of Cameroon via Equatorial Guinea and Gabon to the west of the Central African Republic and the Republic of the Congo . Evidence also comes from the Brazzaville region in the south of the Republic of Congo, while there is no evidence from the Democratic Republic of the Congo , but an occurrence in this country is possible.
Way of life
The Thomas redshank squirrel lives mainly in year-round or seasonally flooded areas in swamps, gallery forests, river forests and on river islands. Preferably the kind Raphia -Sümpfe in Terra Firme -Waldgebieten in Gabon did not happen, however, even if they are in direct vicinity of rivers. In Nigeria, the animals live mainly in the lower areas of the secondary forests and dense bushes.
In their habitats, the animals occur in comparatively dense populations and often live in small groups of up to about six individuals or in pairs, with the animals often traveling together and following one another closely. The couples maintain an intense comfort behavior , they groom each other and rest in close physical contact. Details of the social structure are unknown, but the behaviors described indicate monogamous pairing. Communication takes place via various calls. The animals use a low-intensity call from individual or a few "chucks" as alarm calls; as an intensive alarm call they use a call composed of two to four rhythmic individual calls followed by one or two long, high-frequency whistles ("dada-dada-dadaa ... dadaweeeeeeou" ). Only the long whistle can be heard from further away. In the case of the less intense alarm call, the tail is slapped down against the back from the upright position and then slowly straightened up again, the animals stamping with their back feet and then with their front feet.
They are diurnal and live as good climbers in the branches of the bushes and in low trees and oil palms . They usually look for food on the ground and in the bushes and in trees below 13 meters, on average at a height of about 3.80 meters. They usually build the nests as round leaf and branch nests with a diameter of 20 to 24 centimeters in the dense branches of the bushes and trees, often in the branches above water. They also use plant fibers and raffia leaves as reinforcement and cover for the nests. The animals feed, such as other species of the genus predominantly herbivor of fruits and seeds, about 77% of the food comprise, insects and other invertebrates (about 20%, especially ants and termites), and the green parts of plants and fungi. In raffia inventories directly the animals eat mostly the pericarp of the fruits of palm trees, which they find in the upper regions of the palms. The animals communicate via various calls, including a comparatively low alarm call from a series of "chucks" that the animals utter alone or together. In addition, there is a very loud alarm call consisting of individual calls of different frequencies, which together result in a wobbling call.
The females give birth to one or two pups in one litter, with pregnant females being caught throughout the year in the Democratic Republic of the Congo. The maximum load rate was at the end of the dry season and the beginning of the rainy season in August to October. There is also no information about predators for this species. The animals can be the carrier and reservoir of the simianpox virus.
Systematics
The Thomas redshank squirrel is classified as an independent species within the genus of the redshank squirrel ( Funisciurus ), which consists of ten species. The first scientific description comes from the British zoologist Oldfield Thomas from 1890, who described the animals using individuals from Buguera south of Lake Albert in Uganda as Sciurus pyrropus anerythrus and thus as a subspecies of the firefoot squirrel (today Funisciurus pyrropus ). After it was viewed as a separate species, there was long confusion about the assignment of the various subspecies to the Thomas redshank squirrel and the firefoot squirrel, and some subspecies were pushed back and forth several times.
Within the species, four subspecies are distinguished together with the nominate form :
- Funisciurus anerythrus anerythrus : nominate form, occurs in western Uganda over parts of the Democratic Republic of the Congo to Mount Kabobo and west to the northern tip of Angola . The back fur is reddish-brown, the belly is colored yellow to red or ocher.
- Funisciurus anerythrus bandarum : The subspecies occurs in the Central African Republic to southern Chad . The brown back is washed in with beige-colored hair, the lower abdomen is light gray to beige.
- Funisciurus anerythrus mystax : The form lives in southern Cameroon and Gabon . The back color is reddish brown, the belly orange.
- Funisciurus anerythrus raptorum : The subspecies lives in West Africa in Benin and Nigeria . She has a grayer back color and a whitish belly. It is possible that this is a separate species.
Status, threat and protection
The Thomas redshank squirrel is listed as “least concern” by the International Union for Conservation of Nature and Natural Resources (IUCN). This is justified by the comparatively large distribution area and the assumed large populations of animals in their habitat with occurrence in several protected areas as well as their high adaptability to habitat changes. There are no known threats to the species' existence.
supporting documents
- ↑ a b c d e f g h i j k l m n o p q Louise H. Emmons: Funisciurus anerythrus, Thomas's Rope Squirrel. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume III. Rodents, Hares and Rabbits. Bloomsbury, London 2013, pp. 49-50; ISBN 978-1-4081-2253-2 .
- ↑ a b c d Richard W. Thorington Jr. , John L. Koprowski, Michael A. Steele: Squirrels of the World. Johns Hopkins University Press, Baltimore MD 2012; Pp. 212-213. ISBN 978-1-4214-0469-1
- ↑ Peter Grubb: Genus Funisciurus, Rope Squirrels. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume III. Rodents, Hares and Rabbits. Bloomsbury, London 2013, pp. 46-48; ISBN 978-1-4081-2253-2 .
- ↑ a b c Funisciurus anerythrus in the IUCN 2016-2 Red List of Endangered Species . Posted by: P. Grubb, MRM Ekué, 2008. Retrieved September 12, 2016.
- ↑ Funisciurus anerythrus . In: Don E. Wilson , DeeAnn M. Reeder (Eds.): Mammal Species of the World. A taxonomic and geographic Reference. 2 volumes. 3. Edition. Johns Hopkins University Press, Baltimore MD 2005, ISBN 0-8018-8221-4 .
literature
- Richard W. Thorington Jr. , John L. Koprowski, Michael A. Steele: Squirrels of the World. Johns Hopkins University Press, Baltimore MD 2012; Pp. 212-213. ISBN 978-1-4214-0469-1
- Louise H. Emmons: Funisciurus anerythrus, Thomas's Rope Squirrel. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume III. Rodents, Hares and Rabbits. Bloomsbury, London 2013, pp. 49-50; ISBN 978-1-4081-2253-2 .
Web links
- Funisciurus anerythrus inthe IUCN 2016-2 Red List of Threatened Species . Posted by: P. Grubb, MRM Ekué, 2008. Retrieved September 12, 2016.